Influence Of Soil Nitrogen Concentration And Solar Radiation On Davidia Involucrate Baill Seedlings' Growth

Davidia involucrate is a rare and endangered species endemic to China, it has a high science status in plant phylogeny and geology history change investigation. Using endangered plant Davidia involucrate one-year-old seedlings as the research object, we research about Davidia involucrate leading edge march up to the minute, analysis and summarize the photosynthesis parameters and growth parameters to explore the effects of soil nitrogen concentration and solar radiation to the seedlings which was arranged into different nitrogenxsolar radiation treatments. It is aimed to study the influence of soil nitrogen concentration and solar radiation on the growth of Davidia Involucrate Baill Seedlings. The results show that:(1) high nitrogen concentration can slow down the decrease of net photosynthetic rate which is caused by living in an unsuitable environment; (2) proper direct solar radiation may be beneficial for the Seedlings' growth of Davidia Involucrate Baill, which is ombrophyte; (3) additive nitrogen can compensate the decrease caused by shading, however, this compensation can hardly offset the decrease of net photosynthesis rate.